• 융복합기술연구소 논문집
• /
• 제7권2호
• /
• pp.1-5
• /
• 2017

The rotating electrodynamic wheel over a conductive plate produces thrust force as well as normal force. Specially, separating the conductive plate and spacing apart each part, the lateral stability of the rotating wheel is guaranteed due to the restoring force into neutral position. In this paper, the force characteristics of the electrodynamic wheel rotating over the conductive plate is analyzed using the finite element tool. First, the dominant parameters are identified considering the geometric configuration and the operating condition. And the sensitivity for the parameter deviation is quantified for the high force density. The above topology can be applied as an actuating principle for inter-city train as well as contact-free transfer device.

• Journal of Multimedia Information System
• /
• 제8권1호
• /
• pp.23-30
• /
• 2021

Palmprint has become a popular biometric modality; however, palmprint recognition has not been conducted in video media. Video palmprint recognition (VPR) has some advantages that are absent in image palmprint recognition. In VPR, the registration and recognition can be automatically implemented without users' manual manipulation. A good-quality image can be selected from the video frames or generated from the fusion of multiple video frames. VPR in contactless mode overcomes several problems caused by contact mode; however, contactless mode, especially mobile mode, encounters with several revere challenges. Double-line-single-point (DLSP) assisted placement technique can overcome the challenges as well as effectively reduce the localization error and computation complexity. This paper modifies DLSP technique to reduce the invalid area in the frames. In addition, the valid frames, in which users place their hands correctly, are selected according to finger gap judgement, and then some key frames, which have good quality, are selected from the valid frames as the gallery samples that are matched with the query samples for authentication decision. The VPR algorithm is conducted on the system designed and developed on mobile device.

• 한국지구과학회지
• /
• 제31권1호
• /
• pp.88-94
• /
• 2010

서안경계류의 발생 역학을 이해하기 위하여 간단한 실험 장치와 방법을 개발하였다. 위도에 따른 코리올리 파라미터의 변화(즉 베타효과)를 구현하기 위하여 바닥이 경사진 반 시계 방향으로 회전하는 수조를 이용하였다. 중위도 해양에 작용하는 바람 응력은 수조 상부에서 시계 방향으로 회전하는 원판으로 대신하였다. 수조 바닥의 형태와 수조의 회전 유무의 조합으로 구성된 4가지 실험을 수행하였다. 그 결과, 베타효과가 포함된 실험에서 서안경계류와 유사한 흐름과 스베드럽 영역을 볼 수 있었다. 반면에, 베타효과 없이 일정한 코리올리 힘만 있을 때는 수조 속의 물은 관성류의 특징을 나타냈다. 우리는 또한 회전 유체가 굳어진 것처럼 변한다는 테일러-프라우드만 효과를 확인 하였다. 이 연구에서 개발된 장치와 방법은 베타효과에 의한 서안경계류를 이해하는 데 도움을 줄 것으로 기대한다.

• 조명전기설비학회논문지
• /
• 제28권9호
• /
• pp.99-104
• /
• 2014

This paper presents a unified live-streaming method based on Hypertext Mark-up Language 5(HTML5) for an IP camera which is independent of browsers of clients and is implemented with open-source libraries. Currently, conventional security systems based on analog CCTV cameras are being modified to newer surveillance systems utilizing IP cameras. These cameras offer remote surveillance and monitoring regardless of the device being used at any time, from any location. However, this approach needs live-streaming protocols to be implemented in order to verify real-time video streams and surveillance is possible after installation of separate plug-ins or special software. Recently, live streaming is being conducted through HTML5 using two different standard protocols: HLS and DASH, that works with Apple and Android products respectively. This paper proposes a live-streaming approach that is linked on either of the two protocols which makes the system independent with the browser or OS. The client is possible to monitor real-time video streams without the need of any additional plug-ins. Moreover, by implementing open source libraries, development costs and time were economized. We verified usefulness of the proposed approach through mobile devices and extendability to other various applications of the system.

• 한국산학기술학회논문지
• /
• 제16권1호
• /
• pp.666-670
• /
• 2015

본 논문은 생체신호를 측정하는 팔목부착용 Fitbit Flex상에 구현된 방사패턴 재구성 안테나에 관련된 논문이다. 또한 본 논문에서 제안하는 루프-다이폴 방사패턴 재구성 안테나의 인체 내 부위별 전자파 흡수율 (Specific Absorption Rate; SAR)에 관한 논문이다. 본 논문의 루프-다이폴 방사패턴 재구성 안테나는 두 개의 RF 스위치를 사용하여 서로 반대방향의 두 가지 방사패턴을 구현한다. 방사패턴 재구성 안테나는 블루투스 (Bluetooth) 통신 대역 (2.4 - 2.485 GHz)을 사용하며, 최대이득은 1.96 dBi이다. SAR 시뮬레이션 결과로 블루투스 입력 평균전력 0.04 W가 팔목을 포함하는 인체 내 다섯 개 부위 (두부, 가슴, 배, 등, 팔목)에 입력되었을 때 Federal Communication Commission (FCC)의 기준인 단위 1 g 당 1.6 W/kg을 모두 만족함을 확인하였다. 또한 최대 SAR 값은 두부에서 1.12 W/kg이다.

• 한국기계가공학회지
• /
• 제12권4호
• /
• pp.75-80
• /
• 2013

Single crystal sapphire being used in high technology industry is a brittle material with a high hardness and excellent physical properties. ELID(Electrolytic In-Process Dressing) grinding technology was applied to material removal machining process of single crystal sapphire wafer. Ultrasonic vibration which added to material using ultrasonic table was adopted to efficient ELID grinding of sapphire materials. The evaluation of the ground surface of single crystal sapphire wafer was carried out by means of surface measuring by using AFM(Atomic Force Microscope), surface roughness tester and optical microscope device. As the results of experiment, it was shown that more efficient grinding was conducted when using ultrasonic table. In case of using #170 grinding wheel, surface roughness of ELID ground specimen in using ultrasonic table was superior to ELID ground specimen without ultrasonic table. However, In case of using #2000 grinding wheel, surface roughness of ELID ground specimen in using ultrasonic table was inferior to ELID ground specimen without ultrasonic table.

• 한국수소및신에너지학회논문집
• /
• 제26권2호
• /
• pp.120-126
• /
• 2015

Recently, the ever-increasing use of fossil fuels for rapid industrial development and population significantly caused an environment pollution and global warming such as climate change. So research and development of sustainable and eco-friendly energy have been performed. Especially the interest in nuclear fusion fuel was significantly increased from the developed countries. The system of fusion energy production was tritium separation, storage and delivery, and purification. Republic of Korea is in charge of Storage and Delivery System (SDS) in the International Thermonuclear Experimental Reactor (ITER). Welding part of the SDS bottles for storing the tritium is known to be susceptible to hydrogen embrittlement. In this study, conducted a study for the relaxation of the stability and hydrogen embrittlement of the weld area. The hydrogen heat treatment was processed through the Pressure-Composition-Temperature (PCT) device according to the time variation. Also mechanical properties such as impact test and hardness test according to using the alkaline cleaning liquid for hydrogen embrittlement relief and the fracture was observed by scanning electron microscopy (SEM) after the mechanical properties evaluation.

• 한국인터넷방송통신학회논문지
• /
• 제17권3호
• /
• pp.153-158
• /
• 2017

최근 급속히 진화하고 있는 정보기술 융합과 더불어, 관광분야에 지역 상권 활성화를 도모할 수 있는 새로운 창조관광 모델이 요구된다. 창조관광모델 실현수단으로서, 공간정보, 콘텐츠, 게임, 디바이스, 무선인터넷과 같은 여러 산업분야의 핵심 기술 융합을 통해 지역 관광객 증가 및 상권 활성화를 도모할 수 있는 새로운 관점의 틀이 필요하다. 본 논문에서는 방문객 맞춤형 투어 가이던스를 제공하며, 아웃도어를 대상으로 동기부여 재미 경쟁 보상과 같은 게임화된 투어테인먼트 서비스를 생성 및 제공할 수 있는 게임화 투어테인먼트 서비스 플랫폼을 제시한다. 본 서비스 플랫폼은 지역 관광객 증대 및 지역 상권 활성화를 위해 게임화된 새롭고 즐겁고 유용한 창의적 투어테인먼트 서비스를 창출 및 제공할 수 있는 틀이며, 본 서비스 플랫폼을 통한 스마트 폰 서비스 실증 구현 모델을 제시한다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
• /
• pp.39-39
• /
• 1999

The KSTAR (Korea Superconducting Tokamak Advanced Research) tokamak is a nuclear fusion experimental device for a long pulse/steady-state plasma operation, adopting fully superconducting magnets. In accordance with completion of the basic design of the torus vacuum vessel and the enclosing cryostat, the vacuum pumping and gas fueling basic design has been developed to fulfil the physics requirements. The ultra-high vacuum pumping and sophisticated gas fueling system of the machine is essential to achieve such roles for optimized plasma performance and operation. Recently the vacuum exhaust system using dedicated pumping ports for the vacuum vessel and cryostat has been modified to meet more reliable and successful performance of the KSTAR[Fig. 1].In order to achieve the required base pressure of 5 x 10-9 torr, the total impurity load to the vessel internal is limited to ~5 x 10-5 torr-1/x, while the cryostat base pressure is kept as ~5 x 105 torr to mitigate the thermal load applied to the superconducting magnets. Each KSTAR fueling system will be separately capable of fueling gas at a rate of 50 torr-1/x, consistent with the given pumping throughput. In order to initiate a plasma discharge in KSTAR, the vacuum vessel is filled to a gas pressure of few 10-6 to few 10-4 torr, and additional gas injection is required to maintain and increase the plasma density during the course of the discharge period.

• 한국가구학회지
• /
• 제22권3호
• /
• pp.160-173
• /
• 2011

Increased internet use under a ubiquitous environment may be called as a great human information space revolution followed by Industrial Revolution. This revolution is exerting its significant influence over all the industry as a whole with speed faster than that of any other times. Along with this trend, if furniture design field that leads living culture should fail to jump on this main stream without noticing it, it may be reduced to a unpopular field some day without any sign of recovery. Under this background, this study is intended to recognize a goal aiming at understanding our rapidly changing living environment and leading our way positively. Currently, our surrounding living environment is immersed in computers here and there and Mark Weiser once defined a system that moves in advance before an action as ubiquitous computing and in this respect, I am going to observe a detailed transformation process of space. First nature of the space may be defined as atoms, a physical space equivalent to a spatial element and Bits space that is untouchable is usually called as 2nd space and a combination of atoms and Bits is an intelligent space - 3rd space - that can be intelligible without touching it and finally, this space is called as a ubiquitous space. This spatial transformation is developed by several changes of living environment and we may call it as living trend or interior design trend. Transformation in terms of social perspective, space structural perspective and digital technique perspective may be enumerated. These transformations were surveyed based on its contents being implemented at a future housing exhibition hosted by 5 construction companies along with fusion of information furniture and furniture depending on each housing space. In conclusion, it could be realized that most of the companies were decorating future space by implementing ubiquitous environment as a success factor of future housing market. It may be meaningful to note once again that under an interior environment, a fusion of furniture and information furniture is required considering interior trend elements.